The number you listed only goes to voicemail and lists other numbers for different situations, and goes to voicemail. I'm doing my mom's taxes and she has a CSF 1099R where box 9b says "UNKNOWN". Box 2a also says "UNKNOWN". How am I supposed to get an answer and complete my mom's taxes? Shouldn't the OPM know this information since they are the ones that sent her the form?!?!?!
